Rolling method and a rolling mill for carrying out the method



y 1967 s. E. M. NORLINDH 3,332,269

ROLLING METHOD AND A ROLLING MILL FOR CARRYING OUT THE METHOD Filed March 18, 1963 4 Sheets-Sheet 1 Fl G.l

INVENTOR, SVEN ERIK MALTE NORLINDH July 25, 1967 E. M. NORLINDH ROLLING METHOD AND A ROLLING MILL FOR CARRYING OUT THE METHOD 4 Sheets-Sheet 2 Filed March 18 1963 FIGZ INVENTOR SVEN ERIK MALTE NORLINDH July 1967 s. E- M. NORLINDH ROLLING METHOD AND A ROLLING MILL FOR CARRYING OUT THE METHOD 4 Sheets-$heet 5 Filed March 18 1963 INVENTOR SVEN ERIK MALTE NORLINDH y 25, 5 s. E. M. NORLINDH 3,332,269

ROLLING METHOD AND A ROLLING MILL FOR CARRYING OUT THE METHOD Filed March 18, 1963 4 Sheets-Sheet 4 INVENTOR SVEN ERIK MALTE NORLINDH United States Patent 3,332,269 ROLLING METHOD AND A ROLLING MILL FOR CARRYING OUT THE METHOD Sven Erik Malte Norlindh, Morgardshammar, Sweden,

assignor to Morgardshammars Mek. Verkstads Aktiebolag, Morgardshammar, Sweden, a Swedish jointstock company Filed Mar. 18, 1963, Ser. No. 265,774 Claims priority, application Sweden, Mar. 22, 1962, 3,222/62 Claims. (Cl. 72-233) This invention relates to a rolling mill adapted to roll by employing liftable and lowerable rolls and roll bearing casings as well as fixed roller beds or roller tables.

The invention has as its primary object to combine in a liftable and lowerable three-high roll pair the advantages of the conventional two-high reversible rolling mills and of three-high pairs with tilting table.

The rolling mill according to the invention is characterized in that the entire roll mounting with associated roll adjusting screws, guides and rest bars are adapted to be lifted and lowered (jumped) respectively between each passage of the material and that for reducing the weight of the roll mounting the adjusting screws are adapted to transfer the rolling pressure directly from the one roll bearing casing receiving the rolling pressure to the other roll bearing casing receiving the rolling pressure, and that an axial guide bar is arranged for effecting axial guidance, which guide bar is provided with guide surfaces engaging with the axial guides of the roll bearing casings.

The method according to the invention i characterized in that the roll mounting is elevated and lowered (jumped) respectively between each passage of material by employing fixed roller beds or rolling tables outside of the set of rolls (or roll pair).

The invention will be described with reference to the appended drawings which illustrate embodiments of the invention and in which:

FIG. 1 is a schematic front view of a jump three-high rolling mill with lifting and lowering means and balancing equipment;

FIG. 2 is a schematic end view of a jump three-high rolling mill with associated equipment;

FIG. 3 is a schematic elevation of the rolling mill of FIG. 2; and

FIG. 4 is a schematic plan view of the rolling mill of FIG. 2.

The principle of the jumping three-high stand, is that a three-high roll unit which is driven via long spindles by non-reversing drive machinery, is lifted or lowered between each pass, by means of an eccentric mechanism under the stand. The weight of the whole three-high unit, can be counterbalanced by a compressed air cylinder connected to an accumulator of adequate size so that the stand, when in the bottom position, is overbalanced upwards, while in the top position, it imposes a load on the jumping mechanism.

FIG. 1 shows a jumping three-high pair in lowered position in relation to the height of the roller bed 34 comprising rolls 1, 2 and 3, driven by universal spindles 7, bearing casings 1a, 2a and 3a and restbar 1b, 2b and 3b. The entire roll pair is guided by the stands 21 and balanced by cylinder 23 having its piston rod 22 secured in the restbars 3b of the upper roll. The entire balancing equipment is carried by pillars 27 and beams 28.

The jumping movement is carried out by the gear means 29 with crank webs 30 and lifting arms 31. Reverse braking of the motor 32 i connected by means of limit contacts, and a holding brake 33 retains the motor and thus the roll pair in the adjusted upper and lower position respectively.

3,332,269 Patented July 25, 1967 The pressure in the balancing cylinder 23 is adjusted by a reduction valve 26, preferably in such a manner, that the roll pair is maintained suspended in intermediate position. The volume in the pressure bell 25, FIG. 1, may be adjusted by liquid 24. The compressed air counterbalancing equipment requires only enough air to make up leakage losses. Due to the overbalancing in the bottom position, the jumping machinery is helped on starting upwards and on braking downwards. The condition in top position is equivalent, due to the underbalancing there. The jumping mechanism is thus given some help for starting and braking both in connection with the elevation and lowering.

FIG. 2 show an end view of a jumping three-high mill in lowered position with the rolls 1, 2, 3 and associated bearing casings 1a, 2a, 3a and drive means 1e, 2e, 3e (FIG. 3) and with fixed roller beds 6. FIG. 3 shows the same mill in a side view and FIG. 4 shows it seen from. above. The roll pair is guided in rolling position against the acceleration force of the material by the stands 70 and 71 with vertical guides 70a, FIG. 4, operating in corresponding guides in the bearing casings 1a, 2a, 3a, and 71a oper ating in corresponding guides formed, for example, in the restbars 1b, 2b, 3b.

The rolls are guided in axial direction against an axial guide bar 72 foldable by the cylinder 72c and provided with guiding faces 72a and fulcrum 7212, FIG. 15. The guiding faces 72a engage with the axial guides 1d, 2d, 3d in the roll bearing casings.

The entire roll mounting is supported with the lengthened screws 2 of the intermediate bearing casings on a carrier 79. The upper and lower rolls can be adjusted between the passes to the desired play relative to the intermediate roll by means of the adjusting screw motors 1g, 3g.

The carrier 79 with wheels 80 is supported on rails 81 on a liftable and lowerable table 82 which jumps with the drive mechanism 74, 75, 76, 77, 78 and is balanced by the cylinders 73.

By means of the play mechanism 84 the carrier 79 can be transferred to a roll exchange carrier 85, the liftable and lowerable table being supported on a fixed stand 83 when the crank webs 75 of the jumping mechanism as sume their lowermost position. At certain local conditions, it may be preferable to exchange the roll when the roll pair is in upper position.

For the exchange of roll pairs, the upper and lower rolls 1 and 3 are first played to a certain distance in relation to the intermediate roll 2, and the pair is lowered to lowermost position, so that the table 82 rests upon stand 83.

The coupling heads 1e, 2e, 3e can then be fixed in a holder which maintains them in their positions until they are pushed on the rolls of the new roll pair.

The foldable axial guide bar 72 is folded aside and the play mechanism 84 draws the roll pair to the roll exchange carrier 85 which moves the new roll pair directly in front of the rolling position. The play mechanism 84 draws the new pair into engagement with the couplings 1e, 2e, 3e and the axial guide 72 is folded up. The coupling holders are loosened and the new roll pair is ready for operation.

Thanks to the aforedescribed construction, roll exchange can be carried out very quickly which is of special importance for rolling small quantities.

Compared with three-high pairs with tilting table, the following advantages may be mentioned in favor of jumping three-highs:

(1) It is easier to edge flat sections in jumping threehighs, due to the fact that the material is supported all the time on a horizontal fixed roller bed 6 on both sides of pair 1, 2 and 3 during the edging operation.

When edging flat sections in three-highs with tilting table, it is necessary to edge in upper position, at least on wide sections, as it is not possible to play the lower roll down below the roller top. The flat section must be introduced with the same upward inclination as the tilting table. In that case, the rolls bend the material edgeways, so that the material will get curved on its side and also turned to a spiral, and rolling in subsequent passes will be difficult. It further will be difficult, if not impossible, to obtain the straightness required.

(2) Even in sections other than fiat ones, the material maintains its straightness easier in jumping three-highs than in three-highs with tilting table, because in the latter the material when passing through the tilting table in upper position is bent upwards and downwards.

(3) It is easier to make the material engage between the rolls 1, 2, 3 in jumping three-highs, partly due to the fact that the material follows a horizontal path 6, and partly because it is easier to operate a straight material. In three-highs with tilting table it is not possible to produce the same force for introduction, in view of the upward slope when the tilting table is elevated.

(4) It is easier to mount control rules, bar edgers and other auxiliary equipment in the fixed roller beds 6 when using jumping three-highs than in the case of tilting table.

When comparing them with two-high reversing rolling mills, jumping three-highs show the advantages as follows:

(5) In two-high reversing pairs the guides for semicircular grooves which require about twice as much space as the groove proper, must be removed in the grooves which are not in use at the moment, in order to be able to utilize the entire rolling path for rolling grooves. In jumping three-highs the entire length of the rolling path in lower position may be filled with entry guides for semicircular groove while the space between the semicircular grooves of different dimensions is filled with associated finishing roll grooves and diagonal grooves employed in upper position. The same is the case when sections are rolled.

(6) In jumping three-highs alternate current motors with flywheel may possibly be used, while two-high reversing pairs require expensive direct current motors with Ilgner-Leonard transformer or rectifier.

(7) Jumping three-highs render possible safer rolling in box grooves (rectangular grooves), because the box grooves can be made deeper in lower position and thus provide better control against tilting when the rectangular section is entering after the upward turn. For the second pass after the turn, the box grooves in upper position may be made less deep without risk of tilting.

In two-high reversing pairs the depth of the box groove is determined by the height of the material subsequent to the second pass after the upward turn. Consequently the groove is shallow, so that the rolls must be separated for the first pass after the upward turn, which includes greater risk of tilting. For this reason, it is almost necessary to provide two-high reversing mills with manipulating rules for holding and guiding the material, while in three-high mills with tilting table about the same safety of operation is obtained by employing finger edgers and box-shaped entry guides.

(8) Jumping three-highs render possible safer rolling in that lateral guides (guide boxes) may be used at the entry guide end to prevent the hot rolling material from being engaged by or tilted against a groove flange. In many cases, it is even possible to give the discharge guides a better construction than in two-high reversing mills.

(9) In such cases, where the roll pair is played between each pass, a lower playing speed may be chosen in jumping three-highs than in two-high reversing mills, because there are two intervals and one passing period available for the playing, for example, of the upper roll 3 whilst rolling in the intermediate and lower roll 2 and 1 respectively. Thereby a more accurate setting of the roll pass is obtained.

What I claim is:

1. A rolling mill comprising fixed stand means having elongated guiding surfaces along which mounted rolls can be moved;

work feeding means operative to feed a workpiece in a plane perpendicular to the direction of roll movement;

a set of cooperating rolls mounted in bearing casings having bar means with guiding areas complementary to said guiding surfaces of said stand means;

said bearing casings and bar means constituting a roll mounting;

means for effecting movement of said roll mounting in either direction along said guiding surfaces;

and guide bar means pivotally mounted adjacent said roll mounting, whereby when pivoted adjacent the mounting said guide bar means confines the axial movement of said rolls.

2. A rolling mill comprising fixed stand means having elongated guiding surfaces along which mounted rolls can be moved;

work feeding means operative to feed a workpiece in a plane perpendicular to the direction of roll movement;

a set of cooperating rolls mounted in bearing casings having bar means with guiding areas complementary to said guiding surfaces of said stand means;

said bearing casings and bar means constituting a roll mounting;

means for effecting movement of said roll mounting in either direction along said guiding surfaces;

and guide means integral with the fixed stand means adjacent said roll mounting whereby said guide means confine movement of said roll mounting and hence the axial movement of said rolls.

3. The rolling mill according to claim 1, characterized in that the guide of the roll set in the rolling direction is so constructed that the roll set can be pushed into and pulled out of the guides in the longitudinal direction of the roll and be locked in the rolling position in axial guides for facilitating rapid roll set exchange.

4. The rolling mill according to claim 1, characterized in that the set of rolls includes an intermediate roll provided with adjusting screws which are downwardly extended and supported on a table which table comprises a mechanism for effecting lifting and lowering movements of the table and also equipment for balancing the load of the roll set.

5. The rolling mill according to claim 4, characterized in that the set of rolls comprises at least three rolls disposed one above the other, and in that the entire set of rolls is suspended in a balancing means acting upon the bearing casings of the uppermost roll, and that the means for effecting the lifting and lowering movements act upon the bearing casings of the lower roll.

6. The rolling mill according to claim 5, characterized in that said means for effecting the lifting and lowering movements comprises an electric motor which via gear means actuates a lever system engaging with the bearing casings of a lower roll.

7. The rolling mill according to claim 4, characterized in that the means for effecting the lifting and lowering movements comprises an oil cylinder actuating via a lever system the bearing casings of a lower roll.

8. The rolling mill according to claim 4, characterized in that the means for effecting the lifting and lowering movements comprises an electric motor which via gear means actuates screws for lifting and lowering the roll mounting.

9. The rolling mill according to claim 5, characterized in that it comprises a combined oil-hydraulic lifting and lowering means and a pneumatic balancing means.

10. The rolling mill according to claim 5, characterized in that balancing is carried out with a pneumatic container of such small size that the roll pair is balanced in intermediate position and is overbalanced in lower position and underbalanced in upper position, thereby assisting the means for effecting the lifting and lowering movements in starting and braking masses involved in the rolling operation.

References Cited UNITED STATES PATENTS 6 2,601,794 7/1952 Wood 8055 2,676,502 4/1954 Norlindh 80-39 3,136,182 6/1964 Wegmann et a1. 80l3 FOREIGN PATENTS 5 52,073 1/1923 France.

OTHER REFERENCES Journal of the Iron and Steel Instit., vol. 202, March 1964, Title: Some Outstanding Features in New Swedish Rolling Mill Installations, Norlindh, pp. 271-275.

CHARLES W. LANHAM, Primary Examiner. C. H. HITSON, A. RUDERMAN, Assistant Examiners. 

1. A ROLLING MILL COMPRISING FIXED STAND MEANS HAVING ELONGATED GUIDING SURFACES ALONG WHICH MOUNTED ROLLS CAN BE MOVED; WORK FEEDING MEANS OPERATIVE TO FEED A WORKPIECE IN A PLANE PERPENDICULAR TO THE DIRECTION OF ROLL MOVEMENT; A SET OF COOPERATING ROLLS MOUNTED IN BEARING CASINGS HAVING BAR MEANS WITH GUIDING AREAS COMPLEMENTARY TO SAID GUIDING SURFACES OF SAID STAND MEANS; SAID BEARING CASINGS AND BAR MEANS CONSTITUTING A ROLL MOUNTING; MEANS FOR EFFECTING MOVEMENT OF SAID ROLL MOUNTING IN EITHER DIRECTION ALONG SAID GUIDING SURFACES; AND GUIDE BAR MEANS PIVOTALLY MOUNTED ADJACENT SAID ROLL MOUNTING, WHEREBY WHEN PIVOTED ADJACENT THE MOUNTING SAID GUIDE BAR MEANS CONFINES THE AXIAL MOVEMENT OF SAID ROLLS. 